What we have here, in plain English, is Scotus hocus pocus about Potus. Now that that’s understood, the entire meaning of Judge Samuel A. Alito Jr.’s selection to sit on the Supreme Court should be clear. This shorthand helps us to see that the proceedings in Washington aren’t about the nominee at all; the proceedings are about the man who nominated him. It helps us to see, moreover, that the hearings aren’t about the institution Judge Alito has been selected to join, either; they’re about the institution that put him forward and the institution that will decide whether he gets to sit there.

Clear? Thought so.

But in case it’s not, here’s a key to decoding what this column, and what the Alito matter, are all about. Go back to the first sentence, probably not the most accessible one ever written. “Scotus” is an abbreviation for Supreme Court of the United States. “Potus” is an abbreviation for president of the United States. “Hocus pocus” is an abbreviation for the way we conduct our politics.

What I am trying to say – what, indeed, the principals in the Alito drama are trying to say – is that the hearings on his nomination are not what they look like. They are not really about Judge Alito, his background, his education, his qualifications. They are about the presidency. They are not really about the powers of the judicial branch. They are about the powers of the executive branch. And the men and women who are weighing these questions aren’t merely fulfilling the responsibilities of the Senate as set out in the Constitution. The legislative branch, in deciding on a nomination to the judicial branch, will be making a statement about the executive branch as well.

This rarely happens. Supreme Court nomination fights are usually about the high court and its direction and role in American civic life. Occasionally, as in the case of Robert H. Bork, whose rejection made him the most powerful legal figure not on the Supreme Court, the fight is about the outlook of the nominee himself. Rarely, as in the case of Abraham Lincoln’s selection of Noah Swayne to the court in 1862, a nomination is about a single issue – in that case the Dred Scott decision, which Lincoln deplored as a candidate for the Senate in 1858, as a candidate for president in 1860 and as president in 1861.

Not this time. This time the big issue in American political life is the power of the presidency itself. The terrorist attacks of Sept. 11, the Patriot Act that followed in their wake, President Bush’s decision to go to war in Iraq, the president’s determination to stay the course in Iraq, the disclosure that federal officials have spied on American citizens – all these elements have thrust the presidency to the center stage of the American debate. Not since the Richard Nixon years has the presidency been so prominent a part of our politics.

There are, however, several important differences between the period 1969-1974, when Nixon occupied the White House, and the period after 2001, when Mr. Bush has been president.

One of them, of course, is the feeling of imminent danger that Americans sense today; they felt no such uneasiness during the Vietnam War or during a period when Nixon and his Soviet counterpart, Leonid Brezhnev, were pioneering and practicing the doctrine of detente.

But another difference may be more important, at least for domestic politics. Nixon faced a Congress where both houses had strong Democratic majorities and thus formed a formidable political opposition. Mr. Bush works with a Congress where both houses are firmly in Republican hands and thus the tension between the two branches is merely institutional, not institutional and political.

Two results: The president gets his way more often than Nixon did. The president feels far less need than Nixon did to curb his instincts so as to avoid a battle with Capitol Hill.

The importance of this tension in the nation’s politics today – the importance, in short, of the debate about the importance of the presidency – is at the heart of the Alito hearings.

Thus it is not surprising that special attention is being directed at the judge’s remarks on presidential power from a speech he gave to the Heritage Foundation five years ago (“The president has not just some executive powers, but the executive power – the whole thing”). It is not surprising that the two leading liberals on the Senate Judiciary Committee, Patrick Leahy of Vermont (“This is a time when the protections of Americans’ liberties are directly at risk, as are the checks and balances that have served to constrain abuses of power for more than 200 years”) and Edward M. Kennedy of Massachusetts (“He has supported a level of over-reaching presidential power”) stressed their discomfort with Mr. Alito’s views of the presidency during the early parts of the hearings.

Nor is it surprising that fresh attention is being given to a judicial concurrence rendered by Justice Robert H. Jackson in 1952 in an effort to curb the powers of President Harry Truman, who had argued he had the power to seize the nation’s steel mills, then facing the threat of a strike during the Korean War. This is an especially powerful concurrence in this context because it took issue with presidential powers claimed by a Democratic president and was written by a justice nominated by Franklin Roosevelt and selected by Harry Truman to head the American legal team at the Nazi trials in Nuremberg. In that concurrence, Jackson wrote:

“When the president acts pursuant to an express or implied authorization of Congress, his authority is at its maximum, for it includes all that he possessed in his own right plus all that Congress can delegate.”

So make no mistake about the Alito nomination. The fight is not about him, or about the Supreme Court. It’s about the presidency, and what its role should be in the American political system. It’s about, as Judge Alito himself might say, the whole thing.